1. Field of the Invention
This invention relates generally to door lock devices, and more particularly to determining right or left hand side door installation.
2. Brief Description of the Related Art
Among the more successful assemblies offered for building construction is the pre-hung door assembly in which a door is fully prepared for the reception of latching hardware and is hinged in a door frame so that all the installer need do is mount the door frame within a prepared building wall in order to achieve a properly hung door. The precision with which the door is located and hung within the frame and the accuracy with which the door is prepared for the reception of latching hardware is maintained at a high level by virtue of accomplishing those operations in the factory, with specialized manufacturing tooling, leaving little to chance and to the less sophisticated tools and procedures available to installers in the field.
In order to accommodate the requirement for both right-hand and left-hand openings, it has been necessary to supply pre-hung door assemblies in both configurations, enabling an installer to select the appropriate assembly for a particular installation. The necessity to make available pre-hung door assemblies in both hands essentially doubles the number of assemblies which must be made available by the manufacturer and by the distributor and retailer, requiring larger inventories and the concomitant dedication of greater amounts of space, both for storage and on the selling floor.
However, modular door assemblies present particular difficulties of their own. Specifically, there is scope for confusion as to the handedness of the door. Door sets are not symmetrical, as a door can open on the left-hand side or the right-hand side. In addition, the door can open inwardly or outwardly. It would be apparent that an inward opening door hinged on the left is physically identical to an outward opening door hinged on the right. The same applies to inward opening doors hinged on the right and outward opening doors hinged on the left. However, this presents difficulty in definition, since designers will normally specify, for example a “left-hinged door” which can be of either configuration. It is not unknown for door sets to be supplied to site only to find that the orders have been reversed and further supplies are needed. Examples of complex door assemblies are disclosed in patent literature, for example FR 2268970, US2004/0016182, U.S. Pat. No. 5,832,670 and WO2005/033458. None of these door assemblies offer an effective simple solution for reversing a door in a door frame.
In addition, problems in the installation and design of doors often only become apparent when they are fitted on site. Clashes between nearby doors or between doors and other fittings may not have been noticed at the design stage. If this happens, the door set must often be scrapped and replaced with an opposite door set.